Urine dipstick in a child

Use dipstick testing for infants and children 3 months or older but younger than 3 years with suspected UTI

• If both leukocyte esterase and nitrite are negative:
• do not start antibiotic treatment; do not send a urine sample for microscopy and culture unless at least 1 of the criteria in apply
  • criteria stated by NICE for indication for culture
    • urine samples should be sent for culture:
      • in infants and children who are suspected to have acute pyelonephritis/upper urinary tract infection
      • in infants and children with a high to intermediate risk of serious illness
      • in infants under 3 months in infants and children with a positive result for leukocyte esterase or nitrite
      • in infants and children with recurrent UTI
      • in infants and children with an infection that does not respond to treatment within 24-48 hours, if no sample has already been sent
      • when clinical symptoms and dipstick tests do not correlate
        
        
• If leukocyte esterase or nitrite, or both are positive: start antibiotic treatment; send a urine sample for culture

Urine-testing strategies for possible UTI in children 3 years or older (1)

• dipstick testing for leukocyte esterase and nitrite is diagnostically as useful as microscopy and culture, and can safely be used
  • if both leukocyte esterase and nitrite are positive
    • the child should be regarded as having UTI and antibiotic treatment should be started. If a child has a high or intermediate risk of serious illness and/or a past history of previous UTI, a urine sample should be sent for culture
      
      
  • if leukocyte esterase is negative and nitrite is positive
    • antibiotic treatment should be started if the urine test was carried out on a fresh sample of urine. A urine sample should be sent for culture. Subsequent management will depend upon the result of urine culture
      
      
  • if leukocyte esterase is positive and nitrite is negative
    • a urine sample should be sent for microscopy and culture. Antibiotic treatment for UTI should not be started unless there is good clinical evidence of UTI (for example, obvious urinary symptoms). Leukocyte esterase may be indicative of an infection outside the urinary tract which may need to be managed differently
      
      
  • if both leukocyte esterase and nitrite are negative
    • the child should not be regarded as having UTI. Antibiotic treatment for UTI should not be started, and a urine sample should not be sent for culture. Other causes of illness should be explored

Notes (1):

• evidence showed that a positive urine dipstick test for leukocyte esterase or nitrite in children 3 months or older but younger than 3 years greatly increases the likelihood of finding a positive urine culture. Sending only positive samples for culture offered a better balance of benefits and costs for these children than prescribing antibiotics and urine culture for all children
• the committee agreed that there are concerns about sepsis in infants under 3 months with suspected UTI, and usual practice is referral rather than the GP managing symptoms. So the committee recommended that all children under 3 months should be referred to specialist paediatric care and have a urine sample sent for urgent microscopy and culture

Reference:

1. NICE (September 2017).Urinary tract infection in children: diagnosis, treatment and long-term management